The goal of this continuing research is to characterize the presence and nature of visceral afferent projections to the limbic system and striatal complex. In the present study attention is focused on the hippocampus, amygdala and putamen where unit activity is recorded while shocks are applied to the vagus nerve. A significant number of cells histologically verified to be in hippocampus, amygdala and putamen have responded with variable latencies to vagal stimulation.